68 40hp bigtwin slow to pick up speed

[jake22si]

motor runs good, just slow at accelerating to high speed. I think there is something with the shift linkage where it limits the speed? Once it gets going its fine, but if I go from slow to fast it doesnt kick in right away. I haven't checked the compression yet. I cleaned the carb real good last year.

 

[jimmbo]

Re: 68 40hp bigtwin slow to pick up speed

What are the points gapped at?

 

[jake22si]

Re: 68 40hp bigtwin slow to pick up speed

hmmm, guess i'll have to check that out

 

[jake22si]

Re: 68 40hp bigtwin slow to pick up speed

Seems I have a leaky crank seal, everything is covered in oil under the flywheel. Is the seal replaceable by simply pulling and replacing? The oil coating may have been the issue

 

[jimmbo]

Re: 68 40hp bigtwin slow to pick up speed

That and a loss of crankcase pressure. Points are set at 0.020 inch at high point of cam. Seal should be replaceable but special tools may be required to pull old seal out

 

[jake22si]

Re: 68 40hp bigtwin slow to pick up speed

Any homemade tool ideas to pull the seal or should i just hack it out? I just ordered the new seal and am sure this will fix my oil and acceleration problem.

 

[jimmbo]

Re: 68 40hp bigtwin slow to pick up speed

I once saw seal remover that looked like a piece of threaded pipe that would fit over/around the crankshaft but the end would slip in between the crankshaft and seal. You would rotate it like you were tightening it and it would pull the seal up on the threads. I don't think I would recommend using any old pipe though, it could damage the seal surface of the crank